How to tell if it's airfloat

[Short5]

Okay, I know, it floats in air but hear me out lol. I have been milling BP with a skylighter mill that is modified for a faster turn rate per their instructions. I have a proper charge of lead antimony .50cal balls. I recently made my first batches of charcoal from a pawlonia tree. I made BP and rocket fuel for 4oz. core burners. Wanting to make a fast BP I am thrilled with the results. It is much faster than what I made with commercial charcoal from skylighter and at least as fast or faster than goex based on way unscientifc observation.

 

I cooked the charcoal in a paint can retort, everything went exactly as explained all over the net, my charcoal easily broke into what looked like airfloat using a wood dowel to mash it in the can. I milled it for 4 hours or so and ended up with a perfect load just over the top of the media. Dust floats when working with it, it feels just like the skylighter airfloat, looks the same, but is a bit less "floaty" when handling. This brings me to several questions....

 

1. How do I tell if it is air float? I tried running it through a 100 mesh screen and while I was able to rub it through it really wanted to clog the screen, it did not fall through. Hmmm, I will try with the skylighter AF on a 100 mesh after I type this.

 

2.This has me wondering is it moisture in the charcoal that is making it not "float" much. How hygroscopic is it? How to dry it?

 

3. Is a milled batch of charcoal uniform in size or do people screen it? When I dumped the load through a 12 mesh screen to recover the balls there were a couple small balls of charcoal that did not mill down. I am guessing they were a bit hard and maybe under cooked. I am talking like 3 pieces a centimeter across. That makes me think that a milled batch may be airfloat mixed with coarser wood.

 

Thanks for your thought ~Zane

[dan999ification]

the mill will need to have a uniform [ish] size feed to start with to get even size out. mine certainly does but thats another story.

i screen my charcoal through 20 mesh then 100 mesh whatever doesnt pass goes back to the pestle and mortar this way nothing large will go in the mill, i can process over a pound in an hour alot quicker than my mill but it is dirty work [make some stars while im dirty].

as far as all true airfloat goes once it has passed the 100 mesh mine is probably 40% after some has floated away the rest the mill deals with easily when making comps.

ive never tried that wood in charcoal and dont know if it passes screens easily but i wouldnt worry too much about it myself, as long as it makes bp.

 

dan.

[dagabu]

According to the old snorts, airfloat charcoal is 325 mesh or finer, it has NO grain to it when you roll a pinch on it between your finger and thumb. As far as the question about it being airfloat or not, if you feel that it is good, then it is good.

 

There is no way that screening it through a 100 mesh screen is going to be practical, 20 mesh is plenty for charcoal.

 

Less floaty is the loft of the charcoal, some charcoals have so much lost that they cannot be pressed into a rocket because the fuel will not stay compressed while others compress very nicely and make hard grains. If it makes good BP, make goo rockets, you have achieved a good charcoal.

 

Videos of the 4oz rockets?

 

-dag

Edited July 27, 2011 by dagabu

[MikeB]

Just a few things. Charcoal will take up moisture from the air. Enough so that it will cause your BP to clump in the mill. I will mill the C+S separately, then dry it in a drying box before final milling with the KNO3. Depending on the size of your mill, you really don't need very fine charcoal, dime sized chunks will mill down just fine. Once you know your optimal capacity you can simply load your mill with C+S and let the mill do the job.

[Algenco]

According to the old snorts, airfloat charcoal is 325 mesh or finer, it has NO grain to it when you roll a pinch on it between your finger and thumb. As far as the question about it being airfloat or not, if you feel that it is good, then it is good.

 

There is no way that screening it through a 100 mesh screen is going to be practical, 20 mesh is plenty for charcoal.

 

Less floaty is the loft of the charcoal, some charcoals have so much lost that they cannot be pressed into a rocket because the fuel will not stay compressed while others compress very nicely and make hard grains. If it makes good BP, make goo rockets, you have achieved a good charcoal.

 

Videos of the 4oz rockets?

 

-dag

 

 

uhh, I believe Mike S recently commented that anything that passed a 150 mesh screen was airfloat

[Mumbles]

Lancaster calls anything that passes 150 airfloat. His book actually uses 150 mesh charcoal instead of calling it "airfloat". I thought Mr. Swisher came up with another value though, 200 maybe? It's not important enough for me to look up really. Ball mill the snot out of it and call it a day in my book.

[dagabu]

I know, I know, the Swish is God...

 

I get the number from my clay sources and they publish airfloat as 325 mesh. It doesn't matter to me, I grind for and hour, drop it through a 20 mesh screen then a 60 mesh if I am looking for the coarser stuff.

 

-dag

[Short5]

Thanks for the answers. I am going to just be happy with it as is. It works fine for what I do for now. Screening charcoal kinda sucks lol.

 

 

According to the old snorts, airfloat charcoal is 325 mesh or finer, it has NO grain to it when you roll a pinch on it between your finger and thumb. As far as the question about it being airfloat or not, if you feel that it is good, then it is good.

 

There is no way that screening it through a 100 mesh screen is going to be practical, 20 mesh is plenty for charcoal.

 

Less floaty is the loft of the charcoal, some charcoals have so much lost that they cannot be pressed into a rocket because the fuel will not stay compressed while others compress very nicely and make hard grains. If it makes good BP, make goo rockets, you have achieved a good charcoal.

 

Videos of the 4oz rockets?

 

-dag

Here is a 4 ounce with a bit of titanium in the delay and a D1 comet glued on top. It has a header with D1 stars. I used a little F in a center core made with a wrap of craft paper, stars to the outside wall of the paper canister which is made from 3 wraps of kraft, and a mix of BP coated rice hulls and about FFg size granulated BP for filler. I put a wrap of strapping tape arround it. It worked okay but I am thinking the F was a bit more than I needed for the break as it is not very graceful. It sent the stars out of the frame like bullets leaving a big void in the middle with not much glitter effect.

 

http://shortwave5.smugmug.com/Other/Fireworks-and-Fireworks-video/15779922_ryShP#1403680412_BJ9N2bS-A-LB

 

There are a few more experiments on that page but nothing very good.

[Bonny]

IIRC Ned Gorski considers anything passing 100 mesh to be airfloat. That's all I do. For anything that is going to be ballmilled, I simply dump the charcoal in as it comes out of my meat grinder, anywhere from about 10 mesh to airfloat.

[Algenco]

IIRC Ned Gorski considers anything passing 100 mesh to be airfloat. That's all I do. For anything that is going to be ballmilled, I simply dump the charcoal in as it comes out of my meat grinder, anywhere from about 10 mesh to airfloat.

 

 

yep, the mill will take care of it

[oldguy]

LOL, when it floats out of the BM like a genie, its air float.

 

Wear gloves, old clothing & a surgical mask or respirator working with it.

 

LOL, its hard not to get it all over yourself, especially exposed skin, if you are perspiring at all.

 

 

[Short5]

It floats, and I am happy with it's performance, just not convinced it is 100% equal mesh through out. It acts just like the comercial AF I compared with, even in trying to run it through a 100 mesh screen. When I make BP it certainly is "floaty" out of the mill so I am calling it good Thanks for the help.

[dan999ification]

LOL, when it floats out of the BM like a genie, its air float.

 

Wear gloves, old clothing & a surgical mask or respirator working with it.

 

LOL, its hard not to get it all over yourself, especially exposed skin, if you are perspiring at all.

 

 

 

 

seconded, its worth going to the effort to keep safe and to proscess a sizable batch to cut down the amount of times you have to look like this .

 

dan.

[dan999ification]

It floats, and I am happy with it's performance, just not convinced it is 100% equal mesh through out. It acts just like the comercial AF I compared with, even in trying to run it through a 100 mesh screen. When I make BP it certainly is "floaty" out of the mill so I am calling it good Thanks for the help.

 

 

if you are in any way worried "test" your bp.

 

dan.

[reginaqingqing]

I had the same problem.

[fred815]

What's a simple "good" test??? I've heard of the baseball test but isn't there a simple burn test of some kind??

if you are in any way worried "test" your bp.

 

dan.

[Mumbles]

The attached tester is becoming somewhat standard in the amateur pyro community. What you really have to do is compare your own powder against commercial powder, or a known good batch of your own to try to get some sort of standard to base new batched upon. It's not entirely universal as BP has a big dependence upon atmospheric conditions, but it will put you in the ball park.

pvc bp tester pdf.pdf

[dagabu]

Great, more guys playing with their dongles!

 

-dag

[Algenco]

I have a Dongle that was presented to me by the Master himself for winning our little BP contest last year.

Round 2 this weekend at Waynes World Fall Festival

[Mumbles]

You seem like you win things all the time when you go to club shoots. Maybe I should have stood next to you at the raffle at tri-state.

[Algenco]

You seem like you win things all the time when you go to club shoots. Maybe I should have stood next to you at the raffle at tri-state.

 

The Wife won at Tri state, I earned the dongle